Dana 61 7 bolt axles interchange with 8 on 6.5"?
 

I've been looking for a Dana 61 with 3.31:1 for my 72 F250.
I talked to someone who said that he had a 7 bolt axle Dana 61.
I don't recall ever seeing something of that sort.
Can someone please tell me what that setup would fit and if I can swap my Dana 60 axles into it?

Look for Dana 61's under Econoline's. They will be slightly wider and have to change spring pads positions to match. They are regular 8x6.5". I had one under a 82 Chateau Wagon 15 pack.